Gifted? Oh, Really?

According to a US Census Bureau report, nearly 25% of kids "were in a special class for gifted students or did advanced work in an academic subject." Must be a rather expansive definition of "gifted" - IQ scores of 130+ ("gifted" and "genius" level), being normally distributed, are less than 3% of the population.

Question: If 1 in 4 students are "gifted" or doing "advanced" subject work, why then have SAT scores steadily declined since the early '60's?

I think a lot of the "gifted" labeling is probably motivated by the opportunity to get additional funding more than anything else.